Sorting machine using markers



April 10, 1962 w. H. P. PoULlART ETAL 3,028,961

soRTING MACHINE USING MARKERS 5 Sheets-Sheet 1 Filed April 13, 1959- Attorney April 10, 1962 w. H. P. PouLlART ETAL 3,028,951

SORTING MACHINE USING MARKERS Filed April 13, 1959 5 Sheets-Sheet 2 Inventor W.H.P POULIART G. VAN MECHELEN A Harney April 10, 1962 w. H. P. PoULlART ETAL 3,028,961

SORTING MACHINE USING MARKERS Filed April l5, 1959 5 Sheets-Sheet 3 Inventor W.H.P- POULIART G. VAN MECHELEN By Mo Attorney April 10, 1962 w. H, P. PouLlART ETAL 3,028,961

SORTING MACHINE USING MARKERS 5 Sheets-Sheet 4 Filed April l5, 1959 ITIMII, IQ

Inventor W.H.P. POULIRT G. VAN MEC LEN Attorney w. H. P. POULIART ETAL 3,028,961

SORTING MACHINE USING MARKERS 5 Sheets-Sheet 5 April 10, 1962 Filed April 13, 1959 United States Patent Q 3,028,961 SORTING MACHINE USING MARKERS Willy Hortense Prosper Pouiiart and Guillaume Van Mechelen, Antwerp, Belgium, assignors to International Standard Electric Corporation, New York, N.Y., a corporation of Delaware Filed Apr. 13, 1959, Ser. No. 806,025 Claims priority, application Netherlands Apr. 16, 1958 16 Claims. (Cl. 209-1115) The invention relates to a sorting machine. More particularly, it concerns a sorting machine adapted to the sorting or classification of substantially flat documents such as cheques, punched cards, or any substantially tlat individual carrier able to enclose or generally support such types of documents, this sorting machine comprising a plurality of sorting stages, each of which has two inputs and two outputs, the inputs of one stage respectively corresponding to the outputs of the preceding stage.

Such a sorting machine is known from U.S. application of J. Young, Serial No. 636,309, led January 25, 1957. The two inputs of the rst sorting stage are initially loaded with the documents to be sorted, these being divided in about two equal loads, one for each input of this rst sorting stage. The lirst sequence of documents in this first input is then merged with the first sequence of documents in the other input, and the merged sequence is directed to one of the two outputs of this irst sorting stage and leading to a corresponding input of the second sorting stage. Then, the second sequences respectively appearing at the two inputs of the rst sorting stage are similarly merged to produce a second merged Sequence which is sent to the other output of the lirst sorting stage and leading to the corresponding other input of the next sorting stage. Further sequences of like rank at the inputs of the rst sorting stage are then similarly merged, the resulting output sequence in each case being -directed to the output opposite that taken by the previous merged sequence. The operations at the next sorting stage are exactly similar to those just described and after the documents have passed through a suicient number of sorting stages, there will be only one output sequence appearing at one of the two outputs ot the last sorting stage. The sort is then completed.

ln our U.S. patent application Serial No. 805,800, led April 13, 1959, a sorting machine of this type is also proposed but with the additional characteristic that only two sorting stages are used and forming an endlessiloop sorting machine. This last machine has many advantages. In particular, it takes a limited amount of space since only two simultaneously working sorting stages are needed. Also, whereas the sorting machine of the type disclosed in the above application, Serial No. 636,309, necessitates a number of cascaded sorting stages which is at least equal to logg N, with N representing the maximum number of documents required to be sorted by the machine, in the second above mentioned machine, the xed number of two looped sorting stages can serve in all cases for any number N of documents to be sorted, the only limitation being sufficient space on the two pairs of conveyors linking the two sorting stages, to permit the documents' to be accommodated thereon. Also, the time of sorting now depends on the number of sorting passes which areA needed and not on the time needed for the documents to pass through the maximum number of cascaded sorting stages. This would be the case in the earlier machine since even if the actual sort is iinished as the documents start to iiow from one output of an intermediate stage, these documentsV will nevertheless have to be passed, without actually being sorted, through the CII 3,028,961 Patented Apr. 10, 1962 remaining sorting stages until they are nally delivered by the last one. lt will be clear that the number of required sorting passes is in itself dependent on the initial distribution of the documents to be sorted and also on the number of documents fed to the sorting machine, i.e. the less documents there are, and the nearer is their initial distribution to the desired one, the shorter will be the sorting time. Hence, a very flexible and eicient sorting machine is available.

With the two-stage looped sorting machine described above, upon the sort being finished, the documents can only circulate through one particular input for each of the two stages, said particular inputs of course corresponding to particular outputs or" the other stage to which they are linked by two pairs of conveyors. Hence, this state or" affairs, i.e. absence of documents travelling on one conveyor out of each pair, can be detected, andv steps can be taken to recognize the rst document in the endless single tile of documents going round the two stages, whereby the machine can be stopped with the sorted documents in the required order. However, some time will be required for the recognition of this final desired state of aiairs.

A general object of the invention is to provide suchl sertion of the two markers into the sorting machine every time a sorting operation is about to begin, the two markers being instead initially stored into the sorting machine and being returned to their initial storage positions at the end of the sort after having performed their functions. Then, during subsequent sorting operations they will automatically be made to leave their storage positions as the sort starts.

In accordance with a feature of the invention, a sorting machine comprising two sorting stages, each with two inputs and two outputs, the two inputs of one stage being respectively fed by the two outputs of the other stage and vice versa, with the articles to be sorted initially applied to the two inputs of a sorting stage in series of substantially equal sizes and sorted through each stage in accordance with their sor-ting characteristics, e.g. by merging sequences of like rank appearing at the two inputs and dispatching the merged sequences alternately to one and the other output of the sorting stage, is characterised by the fact that each lot of articles, e.g. documents or document carriers, fed to the sorting machine is accompaned throughout the sort by two markers adapted to go through said two sorting stages in the same way as the articles, said markers being respectively placed behind two series of articles initially applied to the two inputs of a sorting stage, and each of the electrical control circuits for said two stages being adapted to recognize said markers and to always dispatch them to opposite outputs.

In accordance with another feature of the invention, a sorting machinev as characterised above, is further, characterised in that upon a rst marker reaching a sorting stage, it stays there under the control yof the electricaldispatched through said sorting stage, one towards one output and the other towards the other output.

In accordance with another feature of the invention, a sorting machine as characterised above, is further characterised in that, at the beginning of a sorting operation, said two markers are initially in respective storage positions in one of two sorting stages, to which they will be automatically returned after the sort is completed.

In accordance with another feature of the invention, a sorting machine as characterised above, is further characterised in that for said one stage initially containing said two markers, these are only dispatched to the two outputs of said one stage under the control of the electrical control circuit for said one stage upon there being at least one article reaching one of the two inputs of said one stage, and that means are provided to stop said articles from flowing through the other stage upon the sort being cornpleted, whereby upon the tinal single sequence of articles having been delivered through said one stage, said two markers will be returned to and stay in their initial storage positions.

l'n accordance with yet another feature of the invention, a sorting machine as characterised above is further characterised in that the electrical control circuits for said one stage in which the two markers are initially stored is provided with a sequence counter reset each time said two markers pass said one stage and adapted to count the number of output sequences from said one stage between two successive passages of said two markers through said one stage, and more particularly to establish whether no more than four output sequences have flowed through said one stage during a round trip of said two markers, whereby upon said sequence counter indicating no more than four output sequences, on their way to the corresponding inputs of the other stage, stop means will be operated after said markers have gained access to said other stage but prior to the articles behind said markers being allowed to go through said one stage, whereby the final output sequence of articles will be prevented from passing through said other stage and may be positioned ready to be taken out of the sorting machine.

The above and other objects and features of the invention and the best manner of attaining them will be better understood from the following description of a detailed embodiment to be read in conjunction with the accompanying drawings which represent:

FIG. 1, a diagram illustrating the principle of a twostage sorting machine;

FIG. 2, a diagram showing a cheque carrier in one of the four reading positions of the sorting machine;

FIG. 3, a block diagram of the complete electrical control circuits used for each of the two stages of the sorting machine;

FIG. 4, synchronized operating circuits used for each of the two sorting stages; and

FIGS. and 6, wth the latter on the right of the former, the electrical control circuits for each of the two stages of the sorting machine.

FIG. l illustrates the principle of operation of a twostage sorting machine of the type disclosed in our U.S. application, Serial No. 805,800. The normal sorting stage NS includes two input positions A4 and B3 which terminate two corresponding input lanes formed by transverse conveyors each comprising two parallel chains adapted to support and advance cheque carriers 1 of the shape shown in FIG. 2 by their two lateral extensions Z and 2'. Thus, the carriers 1 containing the cheques, such as 3, after having been advanced, will eventually be pressed against the input position A4 or B3 as the continuously moving chains then slide under their lateral extensions from which positions they will be laterally dispatched by edgewise conveying rollers to the respective next positions A3 and B2. Position B2 already constitutes the reading position in which a carrier 1 is shown in FG. 2. On the other hand, position A2 is merely an intermediate position due to the input position A., being fed from the outside A lane.

As the transparent cheque carrier 1 enters the reading position B2, or A2 which follows A3, the piece of magnetic tape 4 which is made part of the cheque carrier 1 and which contains the relevant information pertaining to the cheque 3, will pass across a fixed reading head 5.

Each reading position is provided with an individual photocell arrangement. As the cheque carrier 1 enters the reading position A2 or B2, photocell 6 will have its beam of light interrupted by the piece of magnetic tape 4. This produces a signal which recognizes the presence of the piece of magnetic tape. This is conveniently used to enable a distinction between the ordinary cheque carriers and the special markers which are used to control the sorting operation. ln fact, these markers are simply ordinary transparent carriers which do not contain a cheque and from which the piece of magnetic tape has been removed so that photocell 6 can discriminate them. Only two cf such special marking carriers are needed irrespective of the number of ordinary cheque carriers to be sorted. ln the normal case, with the carrier moving in the direcion of the arrow, after the piece of magnetic tape 4 has interrupted the beam of light of photocell 6, the upper opaque part of the cheque carrier 1 and more particularly the front extension 2 will obscure photocell 7. This signal is used to create a so-called reading authorization which is applied to the electronic control circuits of the sorting machine which are adapted to compare the account numbers of successive cheques of one series to ensure that they are sorted in the right manner. These electronic control circuits are fully described in our U.S. application, Serial No. 805,841, tiled April 13, 1959.

At the time that front tip 2 obscures photocell 7, part 8 of the magnetic tape 4 which actually registers the signals is not yet under the fixed reading head 5. As the carrier 1 progresses, the reading head 5 will now read the signals 8 and these will be able to reach the electronic control circuits. Yet another photocell 9 will afterwards be obscured by front tip 2 and this signal will be used to suppress the reading authorization for the electronic control circuits. This reading authorization permits the isolation of the electronic control circuits from any spurious pulses except during the time the useful information is actually read. Photocell 9, used to stop the reading authorization, plays no part with regard to the electrical control circuits which will be described, but photocells 6 and 7 are used to distinguish between normal and marking carriers, the latter controlling the sorting operation. Whereas photocells 7 and 9 produce an activating signal upon their illumination being suppressed, the opposite is true for photocell 6 which therefore normally delivers an activating signal in the absence of a carrier. But, this activating signal from photocell 6 is gated by that produced by photocell 7, whereby a marking carrier will be detected by the joint action of photocells 6 (lighted) and 7 (obscured).

From the reading positions A2 and B2, the carriers are next moved into the merging positions A1 and B1 from which `the two parallel A and B paths are merged into one. This will permit only two output positions per sorting stage, i.e, C and D.

The test made by the electronic comparator will determine if an A carrier or a B carrier is to be advanced out of the sorting stage and either into the output position C or D.

The sorting machine is arranged to function step-wise under the control of cyclic pulses. During each cycle or step, a carrier in one of the positions shown may be advanced to the next position, as the eventual preceding carrier leaves. For the output positions such as C or D, the advancement during one cycle to the corresponding next position D or E may of course be replaced by a displacement onto the corresponding output conveyor. From the reject positions E or E', which the carriers are allowed to reach if, due to some fault they are not allowed to go on either output conveyor, they are automatically taken out of the sorting closed circuit and merely dropped into a corresponding reject container (not shown). During normal operation, the five Positions such as A2-A4, B2 and B3 for the normal sorting stage NS, are generally each filled with a carrier, while at the same time there may be a carrier in one of the merging positions A1 or B1 and further carriers in positions C, D or E.

A carrier in any of the five positions such as A1, B1, C, D or E for the normal sorting stage NS, will automatically be advanced during a cycle without any further control except in the case of the output positions C or D, wherefrom the carrier can be directed to the corresponding output transverse conveyor by the electronic comparator.

For the five other positions of the stage, the advancement during a cycle of either the cheques in positions ATA4 or the cheques in positions B2, B3 will be determined by the electronic comparator.

The reverse sorting stage RS of the machine is identical to the normal sorting stage NS described above and the corresponding positions have been indicated in HG. 1 with the same references provided with a prime, eg. input position A4 corresponds to input position A4.

The machine will be initially loaded on the two inpu-t conveyors leading to the no-rmal stage NS and more particularly to the input positions A4 and B3, The input load of cheques should preferably be about evenly divided between the two lanes to ensure that the two halves include about the same number of sequences, and that a maximum number of sequences of the same rank on each of the input sides have already a chance to be merged during the rst sorting passes through the normal stage NS. The markers which play an essential part in facilitating the sorting operation are built in, to ensure that they will always be there at the right place at the beginning of a sorting operation. More particularly, when the machine is about to be used, one of the two markers is included in the reading position AZ of the reverse sorting stage RS, while the other marker is included in the other reading position Bz of that stage.

A dotted line has beendrawn across the lanes leading to A4 and B3 to indicate the presence of stop members Vwhich may be used to prevent the cheque carriers resting on corresponding conveyors from being actually advanced to the input positions A4 and B3 by the already moving conveyor chains until start signals are given to the electrical control circuits. The loaded cheque carriers, e.g. batches of 500 on each of the two input lanes leading to A4 and B3 are initially deposited on conveying chains in front of these stop members controlled from a relay Zcr (FIG. 5) and the operation of which will later be described. When this relay is operated as is normally the case before a sorting operation, the stop members prevent the roller extensions 2 and 2' (FIG. 2) of the front cheque carrier from advancing and the conveyor chains merely slide under the bottom parts of these extensions 2 and 2 of all the cheque carriers stacked before the stop members.

As the machine is started, relay Zcr is released, the stops which it controls are raised and the two batches of cheque carriers are driven towards and slightly abo-ve the input positions A4 and B3. The cheque carriers will now be made to advance through the normal sorting stage NS which will perform a first sorting pass.

Initially, as the machine is started, the markers in the reading positions A'2 and B2 and one of which must come behind the batch of cheque carriers leading to position A4 while the other must come behind the other batch of carriers leading to position B3, are not yet advanced. As will be described later in detail, this is only permitted upon the first cheque of one of the .two input batches having gone through the normal sorting stage NS and reaching one of the input positions Ba or A4 of the reverse sorting stage RS. At this moment, the markerswill' be able to advance through RS, one being lifted from the' output position C and the other being lifted from the output position D. k Y

During everyl sorting pass, such as the iirst one through NS, the cheques are advanced until one of the input lanes, e.g. leading to input position A4, no longer contains any cheques but merely the marker. This means that an equal number of sequences have now been taken from the two inputs, have been merged in pairs, and have been dis# tributed alternately to the input lanes leading to the input positions A'4 and B3 of the reverse sorting stage RS. On these last output lanes will therefore appear only about half the number of sequences initially present on the two lanes leading to A4 and B3. As the cheques reach the input positions A4 and B3, they are immediately passed into the reverse sorting stage RS whereby both stages will soon be functioning actively at the same time. Upon one of the markers reaching the input position, such as A2 the remaining sequences on the input lane leading to B3 will be alternatively sent to the input lanes leading to A'4 and Ba respectively. Hence, if the batch of carriers on one side initially contains p sequences while the batch of carriers on the other side contains q sequences, with p q, the normal sorting stage NS will deliver p sequences equally divided (to the nearest integer) between its two outputs. Therefore, after the rst sor-ting pass through NS, the two batches of cheques presented to the two input positions A4 and B3 of RS will either contain exactly the same number of sequences IIJ 2 if p is odd. The first pass has reduced the total number of input sequences from p-l-q to p, and the remaining sorting passes will each time reduce the number of sequences by half, with the usual allowance when the total number of input sequences is not even.

Each time a marker has reached an input position such as A4, it goes into the following reading position such as A2 to be detected so that it may act upon the corresponding electrical control equipment, as outlined above, to make the residual sequence in the other input ow through the sorting stages concerned in such a manner that it will be alternately distributed between the two outputs leading to the other sorting stage. In fact, after the rst sorting pass, in normal circumstances there may only be at most one such residual sequence in the otherV input. When the second marker reaches the other reading position such as B2, the corresponding control equipment for the stage concerned will now take care of sending the if p is even, or

two markers one towards one input of the other stage and the other -towards the other input, with the proviso that for the reverse sorting stage RS, this only takes place upon there being at least one cheque ready to enter one of the input positions A4 or B3.

The electrical control equipment -for the reverse sorting stage RS contains a sequence counter which is adapted to count the number of sequences between two successive passages of the two markers through this reverse sorting stage. This counter is reset as the two markers are sent out from the reverse sorting stage RS. It, when the two markers arrive in the reading positions A'2 and B2, the counter indicates that no more than four output sequences have been distributed to the two outputs through positions C and D', the batches of cheques going respectively to the input positions A4 and B3 will, at most, each be divided into two serial sequences. Accordingly, the normal sorting stage NS will then deliver at most one sequence through C and at most one sequence through D, whereby at the next passage through the reverse sorting stage RS the eventual two sequences of cheques, one

d owing through B3 and the other through A'4, will be merged into the single final desired sequence at the output of the reverse starting stage RS, the sorting operation being thus terminated.

This forehand knowledge by the sequence counter that the sorting operation will be terminated after another double pass through NS and RS may be used to advantage not only to avoid unnecessary sorting passes, but also to avoid the final output sequence flowing at one of the outputs of RS from again reaching one of the input positions A4 or B3. The front cheque could be stopped there in front of and above the input position A4 or B3 but it would then be relatively diflicult to position a take out mechanism for removing the sorted batch of cheques from the sorting machine.

As soon as the sequence counter finds that there have not been more than four sequences through RS upon the two markers being positioned in A2 and B2 respectively, the corresponding control equipment for RS sends out th: two markers towards A4 and B3 respectively.

But, from the moment the two ymarkers are sent out of RS, a timing mechanism will be started to operate relay Zcr after a time suicient to ensure that both markers have passed the respective stops located on the conveyors paths somewhat ahead of A4 and B3 and controlled by this relay, so that the markers can still follow their respective batches of cheques. In this manner, as the cheques will be delivered by RS during the final sorting pass, Ithey will not be allowed to proceed beyond the stops and the take out mechanism can readily lift out the sorted batch of cheques from the machine upon the sort being completed.

It will be appreciated that the cheques are loaded in the input lanes leading to the normal sorting `stage NS and they also always appear on these lanes at the end of the sorting operation, which means that the same mechanism can be used to deposit them on the conveyors chains at the beginning of the operation and to lift them out from the conveyors chains at the end of the sort. Moreover, so that the same containers can be used to feed the cheques into the machine and to take them out, the control equipment for the reverse sorting stage RS is also adapted to make one special forced switch-over of the output during the last sorting pass so that the sorted single sequence of cheques is about evenly divided into the two lanes. In this way, the two half batches of sorted cheques will be found, at the end of the sorting operation, in the same respective positions as the two unsorted half batches of cheques were initially put. To this end, the control equipment RS, as it controls the last Isorting pass, takes care that the last final sequence of cheques is sent out from output postiion D', and a line has been sho-wn to cross the output lane from D to indicate that a photocell apparatus is arranged to react upon about half the total of cheques now pressing against the stops on the lane leading to input position A4. This photoceli arrangement controls the release of the output relay 0dr for the reverse stage RS, whereby the release of this relay causes the remaining cheques now to flow out of RS through the other output position C.

An additional advantage of the sequence counter for RS is the following: normally as the first cheque of a series coming through one input reaches the corresponding reading position such as B'2 for the reverse sorting stage RS, this first cheque is read, and the control equipment now takes care to advance the cheques on the other input leading to the corresponding reading position A2 until a cheque enters this position and is read. lf the sequence counter for RS, as the two markers are positioned into the corresponding reading positions A'2 and B2, detects that there has not been more than two output sequences, one is certain that these two sequences will be merged into one by next going through the normal sorting stage NS which will therefore deliver only the single finished sequence at one of its outputs C or D. Hence, the

sort is already completed in such a case, but it is convenient that the cheques should still travel through RS so that they will eventually always reach the same positions to be taken out of the machine. However, the final sequence coming out of say output position C would see its first cheque reach the corresponding reading position B2 and be stopped there until one cheque comes into the reading position A'2. Since the sorting operation is finished at the output of NS, one would have to wait until the complete series of cheques had passed through the output position C of NS, to finally see one of the two markers, sent out through output positions C and D, reach the input position A2 where it could be recognized and permit the finished single sequence to fiow out of RS. The sequence counter can be made to prevent such a state of affairs. Upon having detected that there had been no more than two sequences flowing out of RS, as the cheques fiowing out through only output position C or output position D arrive at the reading positions B2 or A2, the control equipment for RS will cause them to be passed immediately towards the output position C without waiting for a cheque, i.e. one of the markers, to arrive in the reading position A2. In this way, despite the facility of always having the sorted cheques delivered at the output of RS, a possible delay amounting to a sorting pass is avoided.

The details of the above operation will now be described.

Considering FIG. 3, the complete electrical control equipment MJS for the reverse sorting stage RS is shown to comprise two main circuits: the control circuit CL and the synchronizing circuit SY, respectively shown in detail in FEGS. 5 and 6, and in FIG. 4. The control equipment MJS for the normal stage NS is identical to circuit MJS' except that the connections in dotted lines are not used for the normal sorting stage, but exclusively for the reverse sorting stage. Some of the terminals of CL which are not interconnected with terminals of SY are shown connected to various other terminals which are not part of the electrical control circuits to be described, but belong to electronic control circuits which are the subject of our U.S. application, Serial No. 805,841. For the purpose of the present description, it will be sufficient to assume binary signals at these terminals, the times of change in value of these signals being defined in the description. The circuits such as MJS also include various keys which have auxiliary functions to be defined later, except K2 which is a general starting key for the sorting stage coucerned. The two contacts of key K2 permit the connection of terminals CLI.,L and CL15 to the push button contact K0 and to the key contact K1 respectively. Depressing push button K0 will permit the momentary application of ground to the terminals CLM both in MIS and in MJS upon the respective master keys K2 having been operated. rhis reset operation should be made before starting a sorting operation or whenever a fault has occurred and the machine is restarted, in the course of a sorting operation. After push button K0 has been depressed, the general master starting key K1 may now be thrown to apply ground to terminals CL15 both in MJS' and in Ml S and again through the master keys K2 for the stages concerned.

Before describing the operations following the successive application of ground to terminals CLM and CL15 with reference to the detailed circuits of FIGS. 5 and 6, the synchronising circuit SY provided for each Stage of the sorting machine and detailed in FIG. 4, will be outlined.

At the bottom of FIG. 4 are shown the various electromagnets which control the advancement and the positioning of the cheque carriers during their edgewise translation movements from the input position A21 or B'3 to the output positions C', or D or eventually to the ejecting position E.

Each of the ten positions, except the reject position E' aoaaoei which need not be provided with any controlling electromagnets, includes a so-called shift electromagnet such as SA4 for the input position Ar, etc., up to SD for output position D. When operated, a shift electromagnet per-V mits the application of a driving roller (not shown) against the cheque carrier, which driving roller in conjunction with an opposite idling roller will permit advance ofthe cheque carrier out of the position concerned so that it enters the next position in which further advancement to permit a correct centering of the cheque carrier in that next position, will be made under the control of a fixed pair of rollers one of which is a driving roller.

The various positions, except A2 B3 and E also include so-called positioning electromagnets such as PA3 for position A'3 etc., up to PD for position D. These positioning electromagnets control a catch member which arrests the front edge of a cheque carrier near the end of the corresponding position, as its rear edge leaves the xed pair of rollers at the entrance of this position. Thus, as a cheque carrier is driven out of the input position such as A4 under the control of SA4 and travels through the next position AQ, under the further control of the fixed rollers at the entrance of A3, it will finally be arrested in that last position and properly centered by the positioning electromagnet PAB in the released condition. The operations are cyclic, and during the next cycle of advancement for the A input, the positioning electromagnet PA3 will rst be operated to permit the cheque carrier to move out of A3 as soon as the shift electromagnet SA3 is subsequently operated. The positioning electromagnet PAS will only be released after the cheque carrier is already fully engaged in the next position A2 in which it will be arrested and properly centered by the release of the corresponding positioning electromagnet PA2.

Apart from the nine shift electromagnets and the seven positioning electromagnets, there are also a pair of socalled drop electro-magnets DA and DB, and a pair of so-called lift electromagnets LC and LD.

When operated, the former are used to control a mechanism dropping the lirst cheque carrier abutting against and slightly on top of the input position such as A., and which was driven there by the continuously moving conveyors interconnecting the two stages of the machine. This input mechanism is fully described in the application of GX, Lens et al., Serial No. 806,286, tiled April 14, 1959. Thus, when a cheque carrier is to be advanced through the reverse sorting stage RS and for instance through the input position A., prior to the operation of the shift electromagnet SA4 the drop electromagnet DA will lirst be energised to cause the first cheque carrier to be dropped into position A4. This is only a transit position, and during the same cycle of operation, the subsequent energisation of SA4 will already be propelling the rst cheque carrier into the next intermediate position A3 in which the cheque carrier will already be found, correctly centered, at the end oi the cycle.

The latter electromagnets LC and LD will be respectively energised towards the end of the cycle so that a cheque carrier having reached the output position C for instance, will be lifted out of this position and onto the corresponding output conveyor' leading to input position B3 of the normal sorting stage NS. It should be noted that the action of the lift electromagnet such as LC is merely a liberating action which makes the cheque carrier ready to be lifted out, but the actual lifting operation by means of a constantly rotating takeout mechanism fully described in the Belgian Patent No. 577,765, will only take place towards the end of the cycle, when the cheque carrier is already at rest and correctly positioned in the output position C.

Each of the seven positions which are provided with a positioning electromagnet, i.e. all positions except the input positions A2 BQ, and the reject position E', also include two microswitch contacts such as kx, one at the entrance of the position and one towards the exit. These contacts are normally open, and upon the cheque carrier having travelled into the position and having been arrested therein, these two contacts should still be open if the cheque carrier is properly positioned. All these contacts are connected in parallel and thereby afford a means for operating an error relay Er if at the end of the cycle at least one of these is still closed indicating that the cheque carrier is badly positioned. Then, the cyclic advancement of the cheque carriers is automatically stopped preventing damage to these and to the sorting machine.

As shown in FIG. 4, all the 20 electromagnets so far described have one end of their windings directly connected to battery, while their other ends may be connected to a commen ground provided at break contact e1 through various cam contacts such as PTI which are cyclically closed during various intervals of time to permit the operation of the electromagnets to which they are connected, such as the positioning electromagnets PC and PD connected to make Contact PT1.

A full cycle of the various cyclic pulses used to operate these electromagnets is represented in the iigure. To give an idea of the times involved, advancement of the cheque carriers at the rate of 3 per second corresponds to a cycle of about 330 milliseconds. The beginning of each cycle starts with a pulse PU due to the closure of contacts PU1-PU3 and transferring the ground at break contact e1 to terminals SY3-SY5. These pulses reach terminals CLN-CLM and are used as probe pulses for examining the condition of circuit CL so as to normally drive a pulse either at terminal CL33 connected to terminal SYg, or at terminal CL3., connected to terminal SYN, and also derive a pulse at terminal CLaq connected to terminal SYq, or at terminal CL38 connected to terminal SYS. The first pulse either at terminal SYS or at SYN, determines whether the cheque carriers in the A positions or in the B positions should be advanced. Either relay Ar or Br which have one end of their windings directly connected to battery therefore receives temporarily the ground at break contact e1 which is applied momentarily to the corresponding terminal SYS or SYN. The relay, such as Ar locks to ground through its make contact a1 in series with the interrupter contact IN1 in the break position and break contact el. Thus, the relay indicating which input should be advanced will remain locked in the operated condition until the end of the cycle, the time at which the interrupting pulse IN will occur, corresponding to the opening of lthe break interrupter contact IN1 which is transferred to the make condition. It is at this moment, the end of the cycle, that the operation of make interrupter contact NI will ascertain that none of the 14 positioning contacts such as kx are closed. lf any such contact is closed, relay Er operates through an obvious circuit, change over contact el moves over to the make condition to suppress the ground which can be momentarily applied to the various electromagnets and which is also used to operate or hold some other relays. At the same time, the closure of make contact e1 locks the error relay Er to ground, this relay having no sufficient time to de-energise during the change over action of-contact e1. At this moment, the cyclic closure of the various cam contacts providing the different controlling pulses will be without ettect and the faulty sorting stage is stopped until the cheque carrier which is wrongly positioned is removed from its incorrect position thereby reopening the closed contact(s) kx and releasing relay Er to return to the normal operating conditions.

v The operation of an input relay such as Ar closes a series omake contacts A2-A7 whereby the drop pulses provided by the closure of the corresponding cam contact DRZ, the shift pulse provided by the closure of the corresponding cam contact SH3 and the positioning pulse provided by the closure of the corresponding cam contact PT4 can respectively be caused to energise the corresponding drop electromagnet DA, shift electromagnets SA3 and SAQ and positioning electromagnets PAZ and PA3. it should be noted however, that the closure of the cam Contact DRI, can only be effective to operate DA upon Ar being encrgised, if make contact ka is also energised.

This malte Contact tu is a micro-switch contact which is only operated upon there being ales cheoue carrier abutting against and on top of e co r ending position ACI. This is to ensure that the olie-gue carrier coming from the input conveyor is properly positioned before being acted upon by the input dropping mechanism controlled by the drop electromagne '.huc, if relay Ar is operated at the beginning of a cycie, du; ng the cycle, the various cheque carriers on the A side will all be advanced simultaneously, one being replaced by the next. This is also true for the merging positi since for the latter, the shift and positioning electroma nets SAI and PAI are directly controlled by the corresponcing pulses due to the closure of the contacts SH2 and il?. Obviously, the operation of relay Br would advance the cheque carriers on the corresponding B input side.

vVhen the two markers have reached their respective reading positions AI and B'2, a slightly different operation is required at the inputs. At the beginning of the cycle, the ground input pulse at terminal SY5 which reaches terminal CLI9, will not reappear either at terminal CL33 or CL34, but at terminal CL35 or CLIM; which are respectively connected to terminals SYII or SYI2. In such a case, relay A'r will be operated instead of relay Ar, or relay Br will be energised instead of relay Br. Thcse relays control only the reading positions A2 or B2 which means that only the two markers will be successively advanced during the corresponding two cycles, the upstream cheque carriers temporarily remaining in their respective positions, i.e. the intermediate position Akg or the positions as first cheque carriers of the input series next to the input positions ACI and lEg. The reason for this special advancement limited to t markers is to avoid a complication in the electrical control circuit and which will be discussed later in the description. After the two markers have been dispatched, normal advancement of all the carriers on the A side, or of all the carriers on the B side is resumed.

The pulse at the beginning of the cycle and delivered at terminal SY.I to reach through CL either terminal Sli/7 or SYB, depending on whether the cheque carrier to be advanced is to be lifted out from position C or D' or should be allowed to reach the reject position E', will either operate the clutch electromagnets CC or DC. These clutch electromagnets control a mechanical me ory device which Will store the output to which the cheque carrier is to be directed until the cheque carrier is in the corresponding output position C' or D ready to be lifted out onto the corresponding output conveyor. At the time the pulse at the beginning of a cycle operates CC or DC, the cheque carrier is in the readiru.7 position A2 or B2 from which it will be taken out during the cycle. But, depending on whether the cheque carrier is to leave to the C or to the D output, it will only arrive in the output position C or D two or three cycles afterwards. Thus, it is necessary to memorize the output direction of the cheque carrier during two or three cycles during the next cycle after the cheque carrier has left the reading position, normally anon er cheque carrier will take its place and it will again be required to ener 'ze either CC or DC to indicate the direction to be ,uren by this new cheque carrier. Hence, the electromagnet, such as CC, which also locks to ground through its malle contact ccI will be energised only during part of the cycle and will have its holding circuit interrupted by special interrupter pulse Sl corresponding to the open' of break contact SII. It will be noted that this interrupter pulse is required in View of *he construction of the mechanical memory which neceJ itates a release of CC or DC rather well before the end of the cycle, as shown by the time position of interruptor pulse This mechanical memory may be of the construction fully detailed in Selgian latent No. 577,759. lt consists in ecnanical detents having two stable positions and mounted on a wheel, a revolution of which delinea three cycles, such as one illustrated in FIG. 4. The operation i either CC or DC will trigger a corresponding detent as it passes and the operated detcnt will be used to momentarily close either the make contacts PCI or the make contacts PDI at times shown by thc pulses PC or PD. The contact PCI and PDI are respectively positioned near the periphery of the rotating mechanical memory, so that PCI will be closed one cycle after the operation of CC while PDI is positioned so as to be closed two cycles after the operation of DC. This is one cycle less than the total memory time required, and tr 's is duc to PCI or PDI eing closed at the beginning of a cycle, when the carrier has still to be advanced by one position, whereas the relay Cr or Dr, operated by PCI or PDI, rcspectively, acts to control the lift clectromagnets after the carrier has moved again. He ce, the pulses PC and PD never occur simultaneously but only one of these can be present during a cycle. The make contacts PCI or PDI are used to operate either relay Cr or Dr through obvious circuits, the operated one of these relays locking through its make contact, such as cI, to the ground provided through the interrupter break contact INI. During the subsequent lift pulse Ll in the cycle corresponding to the operation or" the relay, such as Cr, the lift electromagnet, such as LC, will be operated through make contact c2 to place the carrier on the C output lane. Gther- Wise, one cycie later the carrier would be found in position D and through make contact d2, LD would lift it out onto the D output lane. if due to some faulty operation, neither the electromaguet CC or DC is energized, two and three cycles later, neither relay Cr nor relay Dr will be operated and consequently the carrier will be allowed to flow into the ejecting position E from which it will be automatically dropped by gravity into a reject container. Si ift make contact SHI on the other side of the ground provided at break contact eI is connected to terminal SYS either through make contact as or make contact [18. Thus, upon either relay Ar or Br having been energised to af'- vance the A or the B cheques, the subsequent shift pulse SH which follows the disappearance of the pulse PU at the beginning of the cycle and which operated A1' or Bi', will appear at terminal SYS, connected to terminal CLIS to perform various functions in the electrical control circuit CL, one of which being to generate a suitable starting pulse for the electronic comparison circuit. The description of a sorting opeation will now be made with particular reference to FGS. 5 and 6. It is assumed that power has been applied, that the four transverse conveyors are in movement, that the machine delivers the various cyclic pulses required and cXplained above, that the two conveyors leading to input positions A4 and B3 of the normal sorting stage NS are illed wlth carriers each containing a cheque and to be sorted with the account numbers in an order of increasing significance, and that the two markers are in the reading positions A'Z and Bg oi the reverse sorting stage RS. Therefore, the shift electrcmagnets SAI, SBI, SC and SD, ts well the positioning eectromagncts PAI, PBI, PC and PD are already cyclically operated by the corresponding SH and PT pulses. Also, relays lar and Odi' may be opersted or not in both stages of thc machine depending on whether respective activating signais are present at terminals CM1"-L a'nd CMPS (FlG. 3) wh'ch are rcspcctiveiy connected to terminals CLII and CLII leading to one end of the windings of lar and Odi' through the respective amplifying devices lA and OD, the other ends of lar and Gdr being connected to -1-210 volts. As shown for the reverse sorting stage, the direct connection between terminals CLIE and OD and chich is marked v a cross should be replaced by the dotted line connection through break contact zeg of relay Zcr. For

the reverse sorting stage, relay Zcr controlling the stops, was normally energised at the end of the previous soring operation to stop the sorted cheques and initially it is therefore still locked through its make contact zal and break contact sag. Therefore, in theV reverse sorting stage relay dr cannot be initially operated. The arnplifying devices IA and `OD may each consist of a pentode with its grid connected to the input terminal, such as CLM, and limited to a lixed bias voltage, the winding of the output relay, such as lar, being inserted between the plate of this tube and the anode supply of +210 volts. A sutliciently positive signal to energise relay lar or 0dr will be provided from the electronic comparison circuit as long as the comparator indicates that the A input should be advanced thereby operating Ier, or indicates that the D output should be used thereby operating 0dr. The initial potential conditions at terminals CLM and CL12 are in fact immaterial.

With reference to Fl'G. 2, since the two markers are in the reading positions A2 and B2 of the reverse sorting stage, light is cut off from the corresponding photocells 7 as for any carrier in the reading position, but light is still allowed to illuminate the photocells 6, since the empty transparent carrier used as a marker does not bear a piece of magnetic tape which in a normal carrier would obscure this photocell 6. The photo-cell ar rangements of the photocells 6 normally obscured by any other carrier in the reading position, have their outputs connected to terminals CLG and CLq for reading positions A'2 and B2, respectively. Each photocell may be connected in the grid circuit of a triode and have one end biassed to a negative potential so that when it is illuminated, the triode is cut off, whereas it becomes conductive when light is suppressed by the opaque upper part of the carrier reaching the reading position. This input triode may be used as a cathode follower of which an output leads to the electronic comparison circuits after being combined in a mixer with a similar output from the other reading position, and to provide a reading authorization to the electronic control circuits as the inscribed part of the magnetic tape of the cheque carrier is about to go past the iixed reading head. Gn the other hand the cathode output of the input triode may be connected via a further triode cathode follower whose output drives the grid of a pentode arrangement similar to that used for IA and OD.

Therefore, for the reverse sorting stage only, relays Adr and Bar are initially operated.

Upon the reset push-button K3 being depressed, for both sorting stages, ground will reach terminal CLM and the Sar relays will be operated. Break contact S111 ternporarily opens, and any of the six Xar-fr relays which might initialy be operated are instantly released. These relays constitute a counter of 3 which is used to count successive rejects, a pair of these relays, such as Xar, Xbr, being used for each of the three counter stages. This counts oniy consecutive rejects to stop the machine after three such rejects. Every time a cheque is incorrectly sorted, this reject counter makes one step and every time a cheque is correctly sorted, this reject counter is released by the operation of relay Okr opening break Contact okl. At the temporary opening of break contact str2, relay Rkr which might be initially operated and locked through this Contact in series wits its make contact rkl is forced to release. This relay R/cr is operated through make contact rjl of relay Rjr which may itself be operated whenever a cheque is rejected, the operation of Rkr serving to light an indication lamp (not shown) to draw attention to the fact that there has at least been one reject at the sorting stage concerned. At make contact sri-3, ground is applied to relay Sbr which operates, but only as long as relay Sar remains energised by the depression of the reset push-button K0. The temporary operation of relay Sbr applies ground to the mixer M1 which ground appears at the output of this mixer as an activating signal for the gates G2 and G3 whose other inputs are connected to terminals CL2 and CL4 respectively through the amplifier devices AB and BB. Terminals CL2 and CL4 are connected to the photo-cells 6 (FIG. 2) which are normally illuminated and remain so only when a marker, and not a cheque is in the co1- responding reading position. These photo-cells are included in the grid circuit of a cathode follower triode in such a way that they normally provide a suiciently positive signal at the grid to make the triode conductive, the latter being driven to cut olf only when the light is interrupted. Therefore, these photo-cells connected to terminals CL2 and CL4 normally provide an activating signal at the output of the devices AB and BB.

The markers in the reading positions A'2 and B2 of the reverse sorting stage leave those signals and consequently the temporary operation of Sbr will produce pulses at the outputs of G2 and G3 which reach the amplifying devices AB and BB respectively through the mixers M2 and M3. The amplifying devices AB and BB' are similar to IA already described and consequently, relays Abr and Bbr will both be operated for the reverse sorting stage only since make contacts aal and ba2 are closed. The operation of relays Abr and Bbr closes the make contacts abl and bbl which apply ground respectively to the mixers M2 and M3. As the activating pulses at the outputs of G2 and G3 are also constituted by ground pulses, the permanent ground conditions now supplied by contacts abl and bbl are therefore used to latch the corresponding relays Abr and Bbr. Contacts abl and bbl apart from applying holding grounds to the mixers M2 and M3, also apply ground, through the respective decoupling rectitiers RA and RB, to terminals CL1 and CL5 respectively connected to terminals MLA15 and MLB, (FIG. 3) of the electronic control circuit. Therein, these activating signals are used as substitute positioning signals. Indeed, when a normal cheque carrier is read by the electronic comparison circuit, care is taken to verify that the numerical information read is correctly positioned in a shift register. This correct positioning is responsible for authorizing a probe pulse to scan the actual comparator. The positioning of the information should be simultaneously correct in the two shift registers which are respectively used for the A and the B input. Therefore, if a cheque is read while the other reading position is occupied by a mark, the entrance of which has caused the previous information to .be pushed out of the corresponding shift register, the signal at terminal CL1 or CL5 can therefore be used as a substitute positioning authorization.

In operating, relays Abr and Bbr for the reverse sorting stage, also open their break contacts ab2 and bb2 whereby the potential of 250 volts connected to terminals CL30 and CL31 respectively through resistors R1 and R2 is disconnected. Terminals CL3@ and (SL31 lead to terminals CMP15 and CMP21 of the electronic cornparator (FIG. 3). Therein, they lead respectively to two bistable devices parL of the actual comparator and respectively indicating if the account number of an incoming cheque on the A(CL30) or on the B(CL31) side is larger or smaller than the account number of the cheque which is being pushed out ofthe corresponding reading position. This connection of resistor R1 or R2 can be used to elfectiveiy increase the value of a potentiometer resistance part of a bistable multivibrator so as to reverse the state of the latter. These particular resets are carried out so that the bistablev devices will both in`v dicate that the previous account number is higher than that of the cheque which has just entered the reading position.` Thus, whenever a marker comes into a reading position, the comparator is made to react in such a way that the bistable device indicates the interruption of the sequence on the input side corresponding to that marker, which means that only the cheques on the other aus it? input side may eventually continue to build the outgoing sequence.

Normally, an activating Vround prevails at terminal CLZG, being connected through break contacts abs and bbs in series. rthis terminal is connected to terminal IPCEZ (FIG. 3) of the electronic control circuit and the activating signal thereat is normally used to permit recirculation of the account numbers stored in both shift registers of the sorting stage concerned. As a cheque is being read and its account number is serially fed into the corresponding shift register, it is compared with the account number of the previous cheque on that side and which is being simultaneously pushed out of that shift register. But, after this comparison has been performed, the newly sorted account number will now be compared with the account number already and still stored in the other shift register corresponding to the other input. This comparison will again be done serially by causing both shift registers to be looped on themselves and make a full cycle of recirculation.

Whenever a marker has reached the reading position, it must stay there until the other marker also reaches the other reading position. The residual sequence(s) of cheques preceding the second marker must merely be alternately distributed to the two outputs. Therefore, the account numbers of these residual cheques need not be compared with the last account number stored in the shift register for the other input. Recirculation is unnecessary, and the eventual interruption(s) of the sequence(s) of these residual cheques are simply detected at the serial comparison between one cheque and the preceding one on the same side. Hence, upon a marker reaching a reading position, ab3 or bb3 opens whereby -25 volts, which is the standard inhibiting potential for the gates of the electronic control circuit is now connected to terminal CL2@ through resistance R3 instead of the activating ground potential.

At make contacts abr and bbs in series, when both markers are in the reading positions an operating circuit is closed for relay Mar of the reverse sorting stage, through a circuit including also break contact m1 of relay Mr which cannot be operated since the serially connected break contacts ab and bb are opened. Relay Mar locks through its make Contact mal to ensure that it will only be released upon both markers having left the reading positions thereby operating relay Mr. Through make contact bbs, a circuit is established for the operation of relay Djr, which circuit in the case of the reverse sorting stage also includes break contact mln, In operating, relay Djr moves its change-over contact djlvto the make position thereby connecting the armature to terminal CL33. This is however, without effect at this moment since break contact maa opens the connection on the other side of the armature.

A further consequence of the momentary operation of relay Sbr is to open break contact sbz to ensure the release of relay Olr which may be initially locked through its make Contact all. ln fact, for the reverse sorting stage only, the operating circuit of this relay is in errupted by the opening of break contact mam as long as relay Mar is operated. Finally, the opening of 'break Contact sbg interrupts the connection of -25'3 volts which, through resistor R4, is connected to terminals CLT; and CLgS. Again, for the reverse sorting stage only, this connection is also opened at break Contact mag as long as relay Mar is operated.

Terminals (21.27 and CL2@ are respectively connected to terminals CMPIG and ACClg (FiG. 3) of the electronic control circuit, the former connection extending through key K6 in the released condition. This is a reset operation for bistable devices included in the electronic control circuits and carried out in the same manner as already explained in connection with the opening of the connections to terminals CL30 and CL31. Terminal Clviil leads to the bistable device of the electronic comparator indicatffii ing whether the A or B input should be advanced. The opening ot the connection at terminal CL27 will cause this bistable device to indicate that the A input should be advanced. Terminal ACC, leads to two other bistable devices in the electronic control circuit and which must be reset in well defined conditions prior to the beginning of a sorting operation and more generally prior to the beginning of a sorting pass starting each time the two markers are in the reading positions of the sorting stage concerned (mag opened).

When both markers are in the reading positions of a stage, not only must a new sequence be started, but also, since the end of a sorting pass has been reached, a definite set of starting operations must be performed, since when reading the following cheques one must take care that their account numbers are not effectively compared with the account numbers of the last two cheques which preceded the markers on each side and the account nurnbers of which are still stored in the respective shift registers. Indeed, the markers, bearing no piece of magnetic tape with synchronising pulses to advance the shift registers, were not able to push out these last two account numbers. This will be done by the reading of the cheques following the markers but with the help of the reset signals at terminals CL3@ and CL31, the comparator will be made to discard the actual comparisons.

Relay Mar being operated for the reverse sorting stage only, at break contact mag it interrupts the circuits of relays Okr and Err which are respectively connected to terminals CLE, and CLIO through the amplifying devices OK and ER which are similar to IA already described. rhese last. two terminals are respectively connected to terminals CMP, and CMP of the electronic comparator. Each time a new cheque has been read, an end of comparison pulse of about 6() milliseconds appears at terminal CLQ to operate relay Okr. On the other hand, if after recirculating the two account numbers stored in the respective shift registers, these are not properly positioned therein, a pulse of 60 milliseconds will instead appear at terminal CLM, to operate the error relay Err. The sub sequent closure of make contact er1 closes a temporary operating circuit to energize relay Sbr, through terminal CLN, key K4 and terminal CLM. The action is similar to that which occurs at the beginning of a sort, and since relay Oki' does not operate, both carriers are then rcjected in turn. The purpose of opening break contact mag is to ensure that the electronic control circuits cannot in any way, eg. spurious pulses triggering, cause an incorrect control of the two markers when these are both in the reading positions of one stage. At that moment, it is essential that these two markers should be sent to opposite outputs and the electrical relay control circuits are solely responsible for this action.

At make contact muq, a connection between terminals CLN, on the one hand and CL35 or CL36 is prepared to cause t e subsequent advancement of the two markers.

A further consequence of the momentary operation of relay Sur, is the closure of the make contacts Sa4 7 leading respectively to the relays Yar, Ycr, Yer, Ygr via the respective break contacts ybl, ydl, yfl, ylzl. These four relays together with their respective helping relays Ybr, Ydr, Yfr and Y/:r constitute a counter of four, which is the sequence counter used only for the reverse sorting stage, to determine the end of a sorting operation. in operating, the four counter relays such as Ym' lock to ground through their make contacts such as yal, the winding ot their associated helping relay such as Ybr, and break contact :1112 which is connected to terminal CL25 itself connected to ground through key K3 in the released condition. Since the operation of relay Sar is only ternporary, upon its release, the opening of the contacts such as sur; leads to the operation of the four helping relays such as Ybr which are now locked in series with their associated relays such as Yar. In this condition, the se quence counter indicates that the complete load of cheques still comprises more than four sequences and consequently that more than a single round trip through the sorting machine is still necfssary to obtain the finished sorted load of cheques. At the beginning of the sorting operation, such as is now described, this is evidently an arbitrary assumption, since the number of initial sequences into which the load of cheques is divided has not yet been ascertained to be greater than four, as the cheques have not yet been passed through the reverse sorting stage. This assumption is however, quite justified since, with loads of about one thousand cheques to be sorted, on the average these will initially be divided into tive-hundred sequences necessitating nine sorting passes.

' The chances that there would be no more than four sequences initially are therefore extremely remote and even then one could not complain for taking four sorting passes since this is still below the average number of sorting passes required.

Actually, if a mere merging of two loads of cheques is desired, or if it is believed that the two loads initially feeding the two inputs of the normal sorting stage are already sorted, the merging key K3 provided for the control equipment of the reverse sorting stage may be operated to ensure that only a single round trip will be made. This will later be described.

Relay Ygr of the sequence counter bein@I operated, it

will be remarked that relay Mgr has no opportunity to be energised upon the release of relay Sar closing break contact sa when make contacts b9 and bbg are already closed.

A last consequence of the temporary operation of relay Sar is the opening of break contactsag which releases the operated Zcr relay, whereby the stops provided along the lanes leading to the input positions A., and B3 of the normal sorting stage are raised to allow the carriers deposited on these lanes 'to be advanced towards and against these input positions ready to enter them.

The sorting operation will now be started by permanently depressing key K1 to apply ground at terminal CLIE, thereby energising relays Sci' in both sorting stages. ri`he operation of relay Scl' results in applying the start of cycle pulses regularly appearing at terminals CLM), CL2() and CL21 to various circuits through the respective make contacts scl, SC2 and SC3.

A pulse passing through make contact scl is applied to terminal CL33 for the normal sorting stage only, through break contacts r11, mas, stl and djl in the make position. Indeed, for the normal sorting stage, relay Dir must certainly be operated since the bistable of the electronic comparator defining which input should be advanced now indicates the A input and consequently relay Iar is operated closing an operating circuit for relay Djr through make contact ial. The pulse at terminal CL33 reaches terminal SYQ and relay Ar (FIG. 4) is operated and locked. Contact ka (FIG. 4) is closed by the first carrier next to input position A4 and therefore the drop pulse DR energises electromagnet DA to drop the iirst carrier in input position A4 from which it is shifted as soon as electromagnet SA4 is operated by the shift pulse SH. The carrier is further advanced through position A3 in which it will be arrested towards the end of the cycle at the end of the positioning pulse PT causing the release of electromagnet PA3 to stop the cheque carrier in position A3.

As make contact SHI is closed (shift pulse), ground is applied to terminal SYG through make contact a8 and it reaches terminal CL1S to flow through the windings of relays Sdr and Ser in parallel. The first of these relays is however, slow to operate, and consequently relay Ser will operate rst through break contact sdl, this relay Ser releasing as soon as Sdr is energised, and the latter falling back at the end'of the shift pulse SH. The purpose of this circuit arrangement is to restrict the time during which Ser is operated to an interval substantially shorter than that ofthe shift pulse SH, since at its break contact sez, relay Ser causes the initial releaseV of relay Olr, but must allow this relay to be eventually re-energised if the electronic comparison has been correctly performed. This may well take place before the end of the shift pulse SH.

On the other hand, the operation of relay Ser by the shift pulse SH whichv starts after the pulse PU subsides, is useful to ensure that break contact 012 is not prematurely released. Indeed, this contact is connected to make contact .rc3 receiving a start of cycle pulse PU, and this pulse PU should only be able to reach terminal CL39,

and the reject counter, if during the previous cycle relay Various reset operations will take place in these circuitsA before the first cheque carrier on the A input leading to the normal sorting stage NS has had an opportunity to generate a reading authorization pulse for the electronic control circuit by the front tip of the cheque carrier obscuring photocell 7 (FIG. 2). However, during the first cycle beginning with the operation and the latching of relay Ar (FIG. 4) the first cheque carrier on the A input to the normal sorting stage will merely be advanced through the input position A4 to be positioned in the intermediate position A3 at the end of the cycle, the various electromagnets operating in the manner previously described. At the end of this first lactive cycle, interrupter contact IN1 will move to the make position to release relay Ar.

At the beginning of the second cycle, the start of cycle pulse PU will `again flow between terminals CLN and CL33 through make contact dil of the operated relay Djr.

Therefore, relay Ar (FIG. 4) will again be operated and locked to cause the second cheque carrier on the A input to be advanced through input position A4 and to be positioned in the intermediate position A3, while the first A carrier is simultaneously advanced from this last positionv to the reading position A2, by the shift pulse operating SAa (FIG. 4).

During this advancement of the first A cheque, it will thus be read and relay Aar will be energised. The closure of make contact aa, is ineffective to operate relay Abr, since a normal cheque carrier and not a marker has been read. Also, the closure of make contact aa'z comes after the start of cycle pulse passing through make contact sca,

and accordingly, this start of cycle pulse will not be able to pass through break contact 012 of relay Olr which is still released, to incorrectly produce a reject pulse tothe counter of 3.

The electronic control circuits are so arranged that upon the first A cheque having been read, the bistable device controlling which input side should be advanced, will now be automatically set to the B side whereby the signal at terminal CLM disappears.

relay Djr releases also.

At the end of the second active cycle, relay Ar will .l

therefore again be released, but at the beginning of the third active cycle the start of cyclel pulse appearing at terminal CLM, will now iiow to terminal CL34 and from there to terminal SYM, to energise relay Br which locks. Despite relay Aar being still operated and make contact fm2 closed, since changeover contact faz is now in the break position, the start of cycle pulse at terminal CLmwill still be unable to cause an undesired reject pulse v through break contact cl2. During the third active cycle, due to the operation of relay Br, the first cheque carrier This pulse is used t Consequently, relay Iar releases and due to the opening of make contact inl,

weasel on the B input will be advanced, through input position B3 to be positioned at the end of this third cycle into the reading position B2, and after having been read, relay Bar will be energized.

This time, the first B cheque will be compared, in the electronic control circuit, with the first A cheque and if the comparison proceeds normally, an end of comparison pulse of 60 milliseconds will be produced by the electronic comparator at terminal CMPm connected to terminal CL9 to cause the temporary operation of relay Okr. The operation of relay Okr has always two effects: at break contact okl, ground is disconnected from the reject counter of 3 so that if one or more stages of this counter had previously been operated, they are now released since the function of this reject counter is to count consecutive rejects only; secondly at make contact kg, ground is applied to relay Olr which operates and locks through its make contact all. Make contact 0kg also applies ground to the armature of change-over contact cd1. At the beginning of a sorting operation, relay 0dr may be operated or not. Its initial condition is however irnmaterial, since only the changes of output controlled hy this relay matter. Assuming that relay 0dr is initially released for the normal sorting stage, as make contact okz closes, relay Car is operated to indicate that the first outgoing cheque should go to the C output. Relay Car will be maintained energised through make contact all during the remainder of the cycle.

At the beginning of the fourth output cycle, the start of cycle pulse at terminal CLN will now reach terminal CL53 or (SL34 depending on whether after reading the rst B cheque, the electronic comparator found that its account number was larger (ls-'r and Djl' operator) or smaller (lar and Dir released), respectively than that of the rirst A cheque, and the cheque with the smallest account number will, during this fourth cycle, be advanced to the merging position A1 or B1 while the other cheque remains in the reading position Bg or A2, respectively, thecheques on the A side advancing behind the first. The start of cycle pulse at terminal CLZQ will now be able to pass through make contact cal to reach terminal @SL37 connected to terminal SY7. Therefore, the elcctromagnet CC controlling the mechanical output memory previously outlined, will be operated and locked through its make contact cc, in series with the special interruptor contact SI1. The mechanical memory will therefore be set so that one cycle afterwards, a pulse PC will be produced 'oy the closure of make contact PC1. Otherwise, if relay Gdr had been operated, relay Dar and the electromagnet DC would have been energised, resulting this time in the production, two cycles afterwards, of a pulse PD oy the closure of make Contact PDl. Two or three cycles are needed for the first cheque in the A2 or B2 reading position, to be respectively located in the output position C or D. But although the closure of PC; or PDI energises relay Cr or Dr while the first cheque carrier is still in one of the merging positions or in the C output position respectively, the lift pulse Ll, exploiting, by the closure of make contact LI, the closure of make contact c2 or d2 to energize LC or LD, does so after the carrier has made a further step.

At the normal sorting stage NS, the sorting operations described will proceed on the principle of merging sequences of like ranks on both inputs of the normal sorting stage, the merged sequences being alternately sent to one or the other output of the normal sorting stage.

As soon as the first cheque carrier to come out of the normal sorting stage has travelled through the transverse conveyor either linking output position C to input position B3 of the reverse sorting stage RS, or the output position D or to input position Ar of the reverse sorting stage RS, the two markers initially positioned in the reading positions Az and B2 of that reverse sorting stage will be sent away behind the two lots of inputs cheques.

Indeed, upon the first cheque carrier being placed next to input position All, or '6'3 ready to be advanced through these respective positions, either make Contact ka or kb (FIG. 4) will be closed. Hence, the drop pulse DR produced by the closure of make contacts DRZ and DRI will apply a ground pulse either at terminal SYZ or SYI. These pulses are respectively connected to terminals CLZZ or CLM and consequently. either relay Adr or relay Bdr will be temporarily energised. Hence, during the drop pulse DR, either make contact ad, or make contact bfi, will be closed to apply ground from make contact mn, to relay Dm. through make Contact ttbm. This ground is also applied to relay Mlir and finally, through make contact ma to relay Dcr. As a consequence, these three relays Dmr, M111' and Dur are all energised simultaneously. Relay Mbr locks to ground through its make Contact mb, in series with make contact mal, and therefore, the ground connection coming through this last make Contact is now applied to changeover Contact ttbm independently' of make contacts ad, and lidi which are now bridged by make con' tact mbl This is to maintain this ground connection independently of the operation of relay Adr or Bdr which immediately release upon the disappearance of the drop puise DR.

During the next cycle following that which saw the op eration of either relay Adr or Bd." subsequent to the arrival ot first cheque carrier to the reverse sorting stage, the start of the cycle pulse at terminal CLM, will therefore pass to terminal CLg through make contacts sq, m7 and mi in series. Terminal CL35 being connected to termina] SYM, this ground pulse will operate relay Ar which locks in the same way as the ordinary relay Ar. As will be seen from FIG. 4, relay Afr only controls the positioning electromagnct PAB through its make Contact (13 and the shift electromaguet SAE through its make contact d'2. Hence, when the two markers are in the reading positions such as A2, B'2 for the reverse sorting stage RS, when they are successively made to leave these positions, the eleetromagnets controlling the upstream positions such as A3, B3 and A4 are not energised,` contrary to what happens if the normal input relays Ar or Br are energised instead of Az' or Br. The reason for this slightly modified action is the following: Normally, cheque carriers may be present in the upstream positions such as A3 and Bg. Hence, if upon the tirst marker in the A reading4 position being sent away, the following cheque carrier on that side is allowed to replace said marker in the reading position, it will be read in the normal way by the electronic control circuits and as required, a check will be made to ascertain that the account number of the cheque is correctly positioned in the shift register and that there has been no abnormal dispartity between the duplicate normal and inverse forms of recording which may be used as s safeguard. l a fault is recorded for this first cheque following the outgoing marker, it will be necessary to send that cheque carrier to the reject position. Therefore, at the time that the other marker is still in the reading position, the other reading position would be occupied by a cheque carrier which must be sent to the reject position. Normally, this cheque carrier would immediately be advanced through the sorting stage concerned and by replaced by a new one. If this normal procedure is adopted, special memorizing circuits will have to be provided to take care of remembering that the second marker. still in the reading position, must yet be dispatched on the output side opposite that taken by the first marker. Alternatively, the normal procedure of immediately sending the second marker after the first and towards the opposite output, could be followed. But in such a case, special memory circuits should again be provided to remember that the cheque carrier in the reading position must later go to the reject position. Thus, in such a case, the normal simple routines of the machine would be upset, and the proposed solution of simply using relays Ar and Br to temporarily hold the continuous advancement until the Z1 two markers have been dispatched, is a preferred simple solution.

During the next cycle following that which saw the operation of either relay Adr or Bdr, the marker in position AZ will therefore be dispatched to merging position Al, on its way to the D output, since relay Dar has been operated. Upon this iirst marker leaving the reading position, photocell 7 (FIG. 2) is no longer obscured whereby relay Aar releases and by opening its make ycontact aal, it releases the locked relay Abr which in turn, by opening its make contact abb interrupts the ground condition applied at terminal CL, through rectifier RA towards the electronic control circuit. Due to the release of relay Abr, relay Dmr releases and instead, relay Dnr energises through make contact ma., and due to the ground still provided through make contact mal in series with make contact mbl. In this circuit, but through the additional make contact md5, relay Car energises as well.

Hence, during the cycle following that during which the first marker was sent away, the start of cycle pulse at terminal CLIS will reach terminal Clogs through make contacts sel, ma, and dnl in series. This time, this will lead to SYlz and the operation of relay Br. Likewise, the start of cycle pulse at terminal CLZO will now reach terminal CLN through make contacts SC2 and cal in series, taking care of the dispatch of the second marker to the C output, since electromagnet CC (FIG. 4) will now be activated.

As the second marker leaves the reading position B2, relay Bar releases and forces relay Bbr to release with corresponding results to those already described in relation to the departure of the first marker. Apart from the resistors R1 and R2 being again both connected to terminal CL30 and CL31 leading to the electronic cornparator and whereby normal comparisons between an incoming cheque and the one it replaces on the same side can now be made, break contacts aba and bbs being both closed, authorizing ground is again applied to terminal CLZ to permit the simultaneous recirculation of the two numbers stored in the two shift registers of the electronic control circuit, so that these two numbers can be serially compared.

As far as the electrical control circuits are concerned, the immediate result of both relays Abr and Bbr being released is the operation of relay Mr through break contacts ab5 and bb in series. This last relay opens the locked operating circuit of relay Mar at break contact m1, whereby relay Mar releases and in opening make contact mal, causes the joint release of relays Mbr, Dnr and Car.

lt is to be noted that as a result of the temporary operation of relay Dmduring the cycle corresponding to the dispatch of the second marker, break contact dna was temporarily opened. Consequently, the ground normally provided and acting as holding ground for the sequence counter of 4 was momentarily interrupted, resulting in the joint release of the eight counter relays Tar- Yhr. The departure of the two markers therefore leads to the reset of this sequence counter to the zero condition from which it is now ready to count the number of outgoing sequences from the reverse sorting stage RS.

Due to the release of relay Mar, resistor R4 is again connected to terminals CLzq and CL28 leading to the electronic control circuits which are now ready to start with the comparison of the cheques which now follow the two markers through the reverse sorting stage. Thus, the electronic control circuits for the reverse sorting stage are ready to make the second sorting pass at the same time that the first sorting pass is being performed by the normal sorting stage. Due to the opening of contacts ma4, :m and ma, the output relays Car and Dar are now disconnected from the control circuit which initially led to the dispatch of the two markers, and from now on these relays will only be controlled in the normal manner by the electric control `circuits (0kg) until the two markers having made a round trip are again to be found in the reading positions, thus after the two sorting passes, one through each stage and carried out simultaneously. The reopening of make contact maq prevents a further operation of the special input relays Ar and Br, while the closure of break contacts ma and mag again permits the appearance of the start of cycle pulses at terminal CL33 or CL3@ and eventually in case of an error causing a reject, at terminal (SL39. Finally, the closure of break contact mam makes relay Olr ready to be energised after each successful comparison.

During the cycle which follows the departure of the second marker from its reading position B'2 in the reverse sorting stage, the first cheque carrier next to input position A21, if it is there, will be advanced through this input position. Otherwise, if there are only one or more cheque carriers accumulating against the input position Bs, these will have to wait until the first cheque carrier of the second output sequence delivered by the normal sorting stage arrives to close contact ka. The operations will then be identical to those already described as happening initially atV the input of the normal sorting stage: first the A Kcheques will be advanced until the irst can be read, and then Vthe B cheques will be advanced to permit a comparison between the irst A and B cheques,

after which comparison sorting through the reverse sort-I ing stage proceeds normally in the manner already described.

As the cheques are sorted through a stage, one marker will eventually reach the reading position leading to the operation of relay Abr or Bbr. This means that all the cheques on the corresponding input side have gone through the sorting stage concerned, and it is now required that the cheques eventually remaining on the other input side should be automatically dispatched through the sorting stage, which should only detect the ends of input sequences on that side, so that these eventual cheques or residual sequences of cheques on one side can be evenly distributed between the two outputs of the sort` ing stage. Assuming for instance that relay Abr operates, ground transmitted by make contact abl to terminal CLI through rectier RA and leading to terminal MLA15 of the electrical control circuits will take care of giving a substitute positioning authorization in those circuits. Indeed, the end of comparison pulse appearing, after a successful comparison, terminal CLS is conditioned by both numbers being correctly positioned in the shift registers. If the last number to be entered in the shift register and corresponding to the cheque immediately preceding the marker on that side, was not correct, this substitute authorization will therefore ensure that the splitting of the remaining sequences on the other side can still be performed. Rectifier RA is used to prevent that the positioning authorization normally vgiven by the electronic control circuits lshould reach the mixer M2 and cause undesired operation of relay Abr upon a normal cheque carrier being read.

Opening of -break contact abz applies a reset signal to terminal CLau, as previously described, to enable the electronic control circuits to adapt themselves to the me-re splitting of the remaining sequences on the other side. Opening of break contact abs interrupts the ground at terminal CLES to prevent recirculation of the numbers, as previously described, since comparisons between the two opposite sides should no longer be made while the remaining sequences on one side are being split between the two outputs. Opening of break contact ab causes the release of relay Mr which closes its break contact m1 to prepare the energisation of relay Mm' which will however only take place upon the. second l marker reaching the opposite reading position resulting in both contacts ab.; and bb4 being closed.

The opening of break contact abe prevents relay Djr from being operated by the ground provided ythrough make contact inl. Indeed, irrespective 'of the condition of relay lar, since relay Abr has operated upon the arrival of a marker in the reading position on the A side, it must stay there until the second marker arrives into the reading position on the B side. During that time, only the eventual further cheques on the B input side should be advance, and this means that change-over contact di! in the break position should permit the transmission of a start of cycle pulse to terminal CLM to operate relay Br. On the contrary, if the rst marker had entered the reading position on the other side, relay Bbr would have been operated and through make contact bbs would have caused the energisation of relay Djr to permit the start of cycle pulses to be applied to terminal 1.33 to cause the operation of relay Ar. Thus, from the moment a first marker enters a reading position, the further advancement of the cheques eventually remaining on the other side is made independently of the electronic control circuit (lar).

Upon one of the relays Abr or Bbr being operated, during the next cycle, the start of cycle pulse at terminal CL2, will pass through make contact .rc3 and break contact nur@ to operate either relay Aer or relay Bcl' respectively through make contacts abq or bbq. Either of these relays will only lbe temporarily operated during the start of cycle pulse lU (FIG 4) and these temporary operations are used to apply a reset signal either at terminal CL29 due to the opening of break Contact acl disconnecting resistor R6, or at terminal CLN due to the opening of break contact bel disconnecting resistor R4.

In the rst case, the bistable device of the electronic comparator will be automatically and regularly reset to the condition indicating the advancement on the B side, and in the other case, regular resets to indicate advancement on the A side will -be made as required. Thus, as far as the advancement of either one or the other input is concerned, as soon as a marker has entered a reading position, this is now totally independent of the electronic control circuit, since either relay im' must automatically be released by every start of cycle pulse if relay Abr is energised, or relay lar must automatically be operated at every start of cycle pulse if relay Bbr is energised. This is a duplicate for relay Bbr which is provided with two parallel operating paths if relay Bbr operates, and with a double opening of the operating path if relay Abr operates. This ensures that in no case will the marker stored in a reading position be allowed to leave that position before the other marker has also reached the opposite reading position.

Upon the second marker reaching the other reading position, relay Mar is energized through make contacts 11194 and bbl in series and the results will `be similar to those already described in connection with the initial condition of the two markers being located in the two reading positions AZ and B2 of the reverse sorting stage. When the two markers reach the reading positions of the normal sorting stage, there is however this difference that relay Dmr is immediately operated through make contacts bbl, ab4 and abm in series, the ground provided through this connection being also applied to energise relay Dar immediately upon relay Mar operating and closing make contact ma. Hence, in the case of the normal sorting stage, as soon as the two markers are in their respective reading positions, they are immediately dispatched, one to the D and the other to the C output as required, without waiting -for there being at least one cheque carrier at either input of the normal sorting stage.

This supplementary condition for the reverse sorting stage permits the markers to remain in the reading positions of their stage when the sort is liniShed, since the sorted cheque carriers being arrested in front of the normal sorting stage, none will pass the latter to send out the two markers which remain in the reverse sorting stage.

The Asequence counter of four used 4for the reverse sorting stage only, in connection with the determination of the end of the sort will now be described.

It will be recalled that after the initial departure of the two markers from the reading positions of the reverse sorting stage, relay Dnr was temporarily operated, opened its break contact and therefore caused the release of the sequence counter comprising the eight relays Yar-Y/zr. From that moment, the sequence counter of four was controlled by Sqr which is energised from terminal CLE through the amplifying device SQ similar to amplifying device IA. Terminal CL8 is connected to terminal CMPM of the electronic comparator (not shown) and at this terminal, a long pulse of about 60 milliseconds appears every time there is a change of output at the reverse sorting stage. Hence, for every output sequence delivered by the reverse sorting stage, relay Sqr is momentarily operated. This results in the temporary closure of the make contact sql, which applies ground through break contacts mg and ybl to relay Yer which is energised and locks through its make contact ya, in series with the winding of its helping relay Ybr and `break contact duz to the ground provided at terminal CL25 by key K3 in the released condition shown. Upon the reopening of make contact sql, relay Ybr is now energised in series with relay Yar. Change-over contact ybl in the make con dition, now transfers the input operating circuit of the counter, consisting in make contact sql in series with break contact mg, to the `winding of relay Yer through changeover contact vdl of its helping relay Ydr. Thus, relays Ym' and Ybr forming the first stage of thc sequence counter are energised by the first output sequence, relays Ycr and Ydr constituting the second stage of this counter will additionally be energised after the second output sequence has been delivered, and relays Yer and Yfr will then be energised, after three output sequences have been delivered by the normal sorting stage. Relays Ygr and Ylzr will then be energised but only if there are more than four output sequences.

From this moment, the counter may be said to be saturated and further output sequences delivered by the reverse sorting stage can no longer modify its state. The i iportant thing is to know that there are more than four output sequences which have been delivered by the reverse sorting stage, in which case the complete sort can not be possibly finished in a single round trip through beth stages of the sorting machine. Indeed, with the normal sorting stage being fed with more than four input sequences, it will at least deliver three output sequences, two on one side and one on the other, which the reverse sorting stage will not be able to merge into a single output sequence which could be taken out of the machine.

It should be noted that after the last output sequence is delivered by the reverse sorting stage, relay Sqr can no longer be temporarily operated to send a further pulse to the sequence counter of four, since at the moment the second marker cornes into a reading position next to the tirst marker already located in the adjacent reading position, both the parallel contacts abs and bb are open to prevent current ilow in Sqr. This is necessary since when both relays Abr and Bbr are operated, it will be recalled that the consequent openings of break contacts abz and bbz would, together, set the electronic comparator to the end of sequence condition. Hence, as the second marker activates the photocells of the reading position in the same Way as a cheque carrier, a comparator probe pulse is generated and the second marker thus causes a 60 milliseconds end of sequence pulse to appear at terminals CMP24 and CL8 to try and energize Sqr.

If there are no more than four output sequences, when relays Abr and llb/A are both energized by the two markers in their respective reading positions, relays Ygr and Ylzr are therefore not energised and consequently an operating circuit is closed for relay Mgr by applying ground through make contacts abe and Jil/9 in series with break contact ygz. Relay Mgr operates and locks to ground through its make Contact mgl. Through its make contact mgz, an operating circuit is prepared for relay Zar, and eventually for relays Mhr and Aer. Through make contact mgg, the holding ground at terminal CL25 for maintaining the energisation ot the operated relays of the sequence counter of four is duplicated independently of break contact 112. Due to the opening of break contact mgi, the input circuit of the sequence counter of tour is interrupted to ensure that from now on the state of this counter can no longer be modied.

Therefore, from the moment that relay Mgr has operated to close make contact ings, the temporary operation of relay Dur opening break contact duz, and happening upon the second marker being sent oit from its reading position, will not be able to afiect the state of the sequence counter of four, which, otherwise, when there are more than four output sequences delivered by the reverse sorting stage during a sorting pass, results in the reset of this counter of which all eight relays would be deenergised.

In the case of the last sorting pass which is about to begin through both sorting stages and which is now assumed here, one can still distinguish two cases. Either ree or four output sequences were delivered by the reverse sorting stage before the arrival of the two markers in their respective reading positions, or only two output sequences were delivere ln the first case, relays Ycr and Ydr are energised, and in the second case they are not. In the tirst case, the three or four sequences which will be fed to the normal sorting stage during the last round trip will necessarily appear as two sequences at the output of the normal stage and during the last pass, the reverse sorting stage will therefore etectively merge these two sequences into the single 'final sequence. In the second case however, the two sequences at the input of the normal sorting stage will appear as `a single sequence at one or the other input or" the reverse sorting stage, Vas the normal sorting stage performs its merging action. Since at the beginning ot a sorting pass, after two markers have been sent `away from their respective reading positions, an A cheque is tirst advanced to the reading position and then the first B cheque is advanced to the other reading position, the normal sorting stage will issue the single sequence of cheques but the reverse sorting would not be able to deal with it. There would be a waste of time, since the reverse sorting stage which in these circumstances has only to pass the tinal sequence delivered by the normal sorting stage would remain totally inactive while the normal sorting stage delivers that single output sequence. Only the arrival of the marker, the only article on one of the reverse sorting stages inputs could be used to eventually iind out that there is merely the single wanted sequence at the input of that stage, and that this single r'inal sequence must still be passed through that stage to reach the common input/output position of the sorting machine. As will be described, this delay is avoided due to relay Yer being de-energised in these circumstances and eventually permitting the operation of relay Mhr.

In the two cases considered, i.e. on the one hand two output sequences, or on the other hand three or four output sequences, upon the first cheques having been delivered by the normal sorting stage, and having travelled through the corresponding output transverse conveyor sending them to one of the two inputs of the reverse sorting stage, relay Adr or Bdr will be energised and in the manner previously described will result in the two markers being sent away from their reading positions in the normal sorting stage, one towards the D output and the other towards the C outputA Upon the second marker leaving the reading position, contacts [11:5 and [7115 will be closed causing the energisation of relay Mr and the subsequent release of relay Mur as previously described. But, in addition to the operation of relay Mr, relay Zar also operates through make Contact mgg.

The opening of break Contact m1 interrupts the potential of -25 volts previously connected to delay device D1 through resistor R7. This delay device D1 is designed to produce an output signal say l0 seconds after the opening of the break contact za1, this output signal causing the operation of relay Zbr connected at its output. For instance, D1 may comprise a pentode amplifier of which the cathode is grounded through the winding of Zbr. The input grid circuit of this pentode may include a condenser which is normally charged to -25 volts through resistor R1. Normally the potential of -25 volts appearing at one terminal of this condenser is connected to the grid of the pentode which is therefore cut-oit. This condenser plate is also permanently connected through a suitable resistive circuit, so that upon the opening of break contact za1, the grid potential will gradually rise whereby the required delayed operation of relay Zbr may be obtained.

This delay starting from the moment the two markers are sent away from the reverse sorting stage is designed to permit them to advance on their respective transverse conveyors leading to the input positions A1 and B3 of the normal sorting stage NS (FIG. l), so that they are suiiciently near these two input positions by the time relay Zbl' operates. Then, make contact zb1 applies ground to relay Zcr which operates and brings the stops down in front of the input positions A4 and B3, so that the cheque carriers which will now come out of the reverse sorting stage RS will be arrested by the stops ready to be taken out of the sorting machine. As soon as relay Zar is operated due to the departure of the second marker, break contact zag opens and prevents the start of cycle pulses regularly applied at terminal CL19 from eventually reaching terminals CL33 or CL34 to cause the advancement of the cheques at the inputs of the.' reverse sorting stage, and which could otherwisebe p05-,`

'sible as soon as relay Mar releases and closes its breakv It is only after the operation of relay Zar,-

contact mag. subsequent to the markers having arrived near tothe input positions A4 and B3 that make contact zc4 will be;

closed to bridge the now open zag break contact.

This bridging action will however only be effective if4 it is assumed that the series break contact mh3 is still closed and accordingly that relay Mhr has not energised simultaneously with Zar and Mr due to there havingA been only two output sequences delivered by the reversey sorting stage. If three or four output sequences were delivered, from the moment relay Zcr is operated, the

start ot cycle pulse at terminal CL19 is ready to cause the advancement of the cheque carriers through the reverse sorting stage as soon as they start to be delivered on both output sides of the normal sorting stage.

On the other hand, if only two output sequences were delivered by the reverse sorting stage, relay Mhr operates together with relay Zar, and opens make contact mha, thereby preventing the closure of make contact at zc;

cheques appearing either at the A or the B input of the` reverse sorting stage. `lf the single output sequence delivered by the normal sorting stage is sent towards the input position A21 (FIG. l) of the reverse sorting stage, the cheques will be automatically advanced through that input position as soon as they arrive without waiting for the hypothetical series of chequesv at the other input.

On the other hand, if the single output sequences de livered by the normal output stage is sent towards inputA position B3 Iof the reverse sorting stage, the trst cheque`4 carrier arriving next to that position would cause the energisation of relay Bdr as previously described. Hence,

of the temporarily closed make contact bd2 through make the closure of make contact brig will apply ground to operate relay Aer which locks to ground independently Contact del. Relay Aer being operated, change-over contact aez moves to the make condition and the start of cycle pulses at terminal CLIS will now be dispatched to terminal 1.34 through make contact 111/16, also to cause the immediate advancement of the single sequence appearing at the B input of the reverse sorting stage.

In both cases, another etect of the operation of the stop relay Zcr, which locks to ground through make contact zcl, is to move change-over contact ze?J to the make condition. Gate G1 has one of its inputs connected to terminal CLN which is controlled by a photocell arrangement arranged along the transverse conveyor linking output position D to input position A4 (FIG. l). It is located towards output position D' at a distance from the stop controlled by relay Zcr which corresponds to about half the overall thickness of the complete lot of cheque carriers inserted in the sorting machine. The beam of light striking the photocell (not shown) is substantially perpendicular to the direction of advancement of this transverse conveyor, and this beam of light will therefore be interrupted upon there being at least about half the total number of cheque carriers packed on the D output lane from the reverse sorting stage RS (FIG. l), the first cheque carrier beingJ pressed against the stops controlled by relay Zcr. At this moment, the mass of cheque carriers will permanently interrupt the beam of light striking the photocell. Indeed, as long as the cheque carriers flow past the photocell arrangement, without being actually closely stacked together in front thereof, the temporary interruption of the beam of light can be made without effect on the output of the photocell arrangement if the latter is provided With a suitable time constant, so that it can only react after an interruption of the beam of light for a certain interval of time.

Normally, the beam of light which illuminates the photo-cell causes an activating signal to appear at terminal CLN. As there is also an activating ground signal transmitted through resistor R8 at the other input of gate G1, the latter delivers an activating output signal which, from the moment relay Zcr operates is transmitted to the input of the amplifying device D to cause the operation of relay dr. Therefore, irrespective of the initial condition of this relay at the time Zcr energises, the cheques which will be allowed to go out from the reverse sorting stage RS some l0 Seconds after the two markers, will necessarily be delivered to the D output. If relay 0dr was in the released condition at the time Zcr operates, an energising circuit is closed for relay Zdr through break contact cd2 in series with make contact zc5. But, relay Zdr is slow to operate, and accordingly it has no opportunty to energise at that moment, since relay 0dr quickly energises to open the operating circuit of relay 2dr at break contact odg.

From the moment relay Zcr operates leading also to the operation of relay 0dr, an operating circuit is closed for relay Dar, ground being applied through make contacts mhz and zes in series with break contact bhw and change-over contact odl in the make condition. Therefore, relay Dar being permanently operated, the cheques owing through the reverse sorting stage will indeed be accumulated on the D output conveyor. This substitute ground provided for the output relays Car and Dar through make contact mhz is mainly to replace the ground normally provided by the electronic control circuit (not shown) producing the operation of relay Okr and the closure of make contact 0kg, as well as the operation of relay Olr, and the closure of make contact 011, after a successful comparison has been made. Indeed, in the present case of a single sequence already appearing at one of the outputs of the normal sorting stage, there are only cheques on one side, and the electronic control circuits are arranged so that they do not deliver this signal to operate relay Okr unless both numbers are correctly positioned. If the last number to be stored on the opposite side to that on which the cheques are now entered, was not correct, relay Okr would not he operated. The present scheme makes therefore the operation of the output relays independent of the electronic control circuits. This will happen only if the reverse sorting stage delivered only two output sequences prior to the last round trip. ln such a case, the single sequence going through the reverse sorting stage during the last round trip must no longer be sorted and the circuit just described therefore prevents the electronic control circuit, controlling relay Oki', from being elfectve since this is no longer needed. Any faulty influence of the electronic control circuit, preventing the beginning of the nal single output sequence from reaching the D transverse conveyor is again avoided.

Still for the ease when the sequence counter detected only two sequences at the end of a double sorting pass, upon relay Mlzr having been operated and relay Mar having been subsequently released due to the operation of relay Mr (departure of the two markers) relay Mjr Was operated through break contact man and make contact mh, and locked through its make contact mjl. Accordingly, make contact mi2 is now closed.

This has the advantage of maintaining this substitute ground for the output relays Car or Dar when the marker comes into the reading position B2.

Assuming that a single sequence is fed to the A input of the reverse sorting stage, as some cheques still pass through that stage, the marker on the other side, the B side, may arrive next to the input position B'3 and cause the operation of relay Bdr and in turn, that of Aer. Due to change-over contact nez moving to the make position, the advancement of the cheques at the A input will now be stopped until the marker on the B side reaches the reading position B2 and causes the operation of relay Bbr moving change-over contact bbw to the make position. The operation of relay Bbr opens break contact bb5 thereby releasing relays Mr, Zar, Mhr and Aer but the opening of make contact mhz will remain without effect, the substitute ground being still provided through make Contact mjz. This ensures that the single sequence of cheques continues to be delivered at the output of the reverse sorting stage.

From the moment that a marker is in the reading position such as B2, relay M/lr being released, the start oi cycle pulse CLIS will again reach either terminal CLES or CLM through break contact mhs. Thus the advancement of one or the other side is again under the control of relay Djr. lt is to be notcd that this relay together with relays Dfnr and DmA had their battery connections interrupted by the opening of break contact 111114 as long as relay Mln' was energised. This is merely a safeguard to ensure that these relays can never be energiscd to control the advancement of one or the other input, while this advancement is controlled through the start of cycle pulse at terminal CLM, passing through make contact zc. In the present case since Bbr was operated, Djr is cnergised through make contact bbs, and the single sequence of cheques on the A side continues to advance. In the reverse case, when a single sequence of cheques appearing at the input of the reverse sorting stage is on the B side, if the marker is eventually dispatched to the A input while the cheques are still passing through the reverse sorting stage, this marker on the A side will be unable to go through input position A4. This is because relay Aer was operated and locked due to relay Bdr being energised by the iirst cheque at the B input, and accordingly the start of cycle pulses continue to be transmitted to terminal CL3., to continue the advancement of the cheques, the marker on the A side remaining next to the input position AC1. This means that relay Miu' remains operated until the marker input.

on the B side reaches the reading position B2, operates Bbr, causes the release of several relays including Mhr and the Operation of relay Dj:- through make Contact bbs to nally advance the marker on the A side to the reading position A'2.

After a sufficient number of cheques, i.e. about half the total lot, have been accumulated on the output conveyor on the D side of the reverse sorting stage, the photo-cell arrangement will no longer be able to supply an activating signal at terminal C1213 and consequently relay dr will be released. From this moment, the cheques will be delivered to the C output of the reverse sorting stage, this time not because there is a change of sequence but merely in order to split the distribution of the sorted cheques between the twol conveyors at the input of the normal stage. The release of relay 0dr closes an operating circuit, through break contact odg, for slow to operate relay Zdr which eventually energises and applies the inhibiting signal of volts through its make contact zdl to the input of gate G1 connected to resistor R8. This is in efr'ect a locking action for gate G1 designed to prevent an eventual renewed delivery to the D output side. rl`his could for example happen if the sorted load or cheques at the D output was removed While the remainder of the sorted cheques was still being accumulated at the C output. Then, G1 would again give an output signal which would cause an undesired shift back to the D output.

At the end of the sort, when both markers are in their respective reading positions A'2 and B'Z, relay Mar energises as previously described and causes the release of relay Mir.

lf during the last pass, the normal sorting stage delivers two sequences, one on each side, the operations will be substantially as detailed above, except of course that as in the case of a normal sorting pass, the irst sequence delivered to one input of the reverse sorting stage will l,have to wait until the other sequence arrives at the other Since relay Ycr is energised, neither relay Mh, nor Aer can be operated, and though relay 0dr will first be operated and then released under the control of the forced splitting arrangement described above, the actual operation of Dar and then Cnr will be controlled by conf tacts okz and al1, While the iinal advancement of the cheques through the reverse sorting stage will be controlled by Djr.

Various miscellaneous features will now bediscussed.

The reject counter of three receives a pulse through break contact cl2, at the start of each cycle, whenever relay Olr was not energised during the previous cycle, thus indicating a faulty condition. It will be remarked that at certain moments, relay Immay be in the energised or released condition to indicate the advancement of the cheques at the A or at the B input of a stage respectively, but without there being actually cheques ready to advance into the corresponding reading position. This may happen for example at the beginning of a sorting pass. It such empty positions occur, it is undesirable to send a reject pulse due to the nonoperation of relay Olr during a cycle and this is prevented by the open make contacts aaz and bag which are only closed upon there actually being a cheque in the reading position. This circuit to the reject counter of three is also interrupted by break contact mag as soon as relay Mar has energised to indicate that the two markers have reached their respective reading positions. Until both markers have left the reading positions, relay OIr cannot be energised and one should thereforeA avoid sending a reject pulse. As soon as a single reject pulse occurs at a sorting stage, relay Rjr operates temporarily in addition to the counter of three and causes the energisation of relay R/cr by closing its make contact rjl. Relay Rkr operates and locks through its make contact rkl in series with break contact sag. This last operated relay may control a lamp circuit (not shown) to indicate that there has been at least one reject at the stage concerned during the sorting operation.

If there are three consecutive rejects, the third reject pulse will cause the operation of relay Xfr which closes its make contact xfg to operate relay Rlr. Relay Rlr is a general release relay which opens its make contact rll, thereby preventing the start of cycle pulse from reaching terminal SL33 or CL23 to continue the advancement or the cheques. From the moment the release relay Rlr operates at one stage, that stage is effectively blocked since the cheques can no longer advance through it.

It should be noted that the interruption of this advancement circuit does not apply to the reverse sorting stage in case relay Mhr is energised to indicate that during the last sorting pass only a single nal sequence of cheques streams out of the normal sorting stage. In such a case, the cheques passing through the reverse sorting stage are not actually sorted therein but merely transfer-red to the final output position.

It will be recalled that the cheque is sent to the reject position it it was badly read, while on the other hand, if there is an error after the electronic control circuits have recirculated the account numbers corresponding to. the two cheques in the two reading positions of any stage, a pulse appears at terminal CMPE to -be applied to terminal CLM), causing the operation of relay Err and the subsequent reset of t le electronic control circuits. In such a case, the actions are equivalent to those happening at the ybeginning ot a sorting pass and both cheques will be rejected. Even this double reject will be insuhcient to cause the operation of relay Rlr and stop the corresponding sorting stage, but if this type of error Ais consecutively repeated, then the sorting stage concerned will cease to function. Hence, errors of a transient .nature will generally not stop a 'sorting stage, whereas the consecutive repetition of errorsrgenerally'indicating some permanent fault would result in the sorting stage concerned being disabled.

Various lamps (not shown) may readily be added to the circuits described in order to give suitable indications on the operation of t" Apart me machine to an operator. from the lamp mentioned above and which may be lighted due to the operation of relay Rkr to indicate that there has been at least one reject at the corresponding stage, one may also add other lamp circuits to indicate for instance that the machine is on, or is out of order. Moreover, it would be useful to include a lamp which is lighted to indicate that the machine is performing the last sorting pass and that the sorted cheques will soon be available. This last pass lamp circuit may be energised upon relay Zar being operated, a'make contact (not shown) of this relay used to close the lamp circuit being paralleled with a further make contact (not shown) of relay Zcr. This is necessary, since although relay Zar operates first, in the reverse sorting stage, it will subsequently be released when the iirst marker comes into its nal reading position in the reverse sorting stage, Whereas relay Zcr remains locked in the operated condition at the end ot the sorting operation.

For each sorting stage or for both, a lamp may also be added to be lighted upon relay Err being operated, to indicate that a cheque carrier is not correctly centered in one of the various positions 'of the sorting stages. Finally, in both stages, the relays Rlr may also light a corresponding lamp when they are operated' to indicate that the corresponding sorting stage has been disabled.`

Whenever a fault has occurred, the reset push buttons K0 should always be operated to energise the correspond'- ing relays Sor with the consequences previously explained. ln particular, this action will permit the recognition of the fact that, at the time of the fault, e.g. a power failure, a marker was standing in one of the reading positions. Then, the closure of make contact sbl will produce a substitute reading authorization forfthe marker standing in the reading position and the corresponding relay Abr or Bbr will be energised. This facility is due to the cheque carriers acting on the photocell, 

